Leather-skiving machine



(No Model.) 3. Sheets-Sheet 1.

A. J; TEW KS'BURY. LEATHER SKIVING- MACHINE.

No. 517,631. v Patented Apr. 3, 1894.

'A. J. TE'WKSBURY. LEATHER SKIVING MACHINE.

3 SheetS- Sheet 2.

' No. 517,631. Patented Apr. 3, 1894.

v. AV/$55557 I Mm I 7 4 NiTE- TATES ATENT tries.

ANDREW J. TEWKSBURY, OF HAVERHILL, MASSACHUSETTS.

. LEATHE R -SKIVING MACHINE.

SPECIFICATION forming part of Letters Patent No. 517,631, dated April 3,1 894. Application filed August 28,1893. Serial No.4s4,193. (No model.)

To atZZ whom it may concern.-

Be it known that 1, ANDREW J. TEWKSBURY, of Haverhill, county of Essex,State of Massa chusetts,'have invented an Improvement in Leather-SkivingMachines, of which the following description, in connection with theaccompanying drawings, is a specification, like letters and figures onthe drawings representing like parts. I

This invention has for its object to improve the construction of leatherskiving machines, especially adapted for skiving upper leather, wherebythe material or skiving is removed on a continuous bevel from the fullthickness of the stock to the edge, with little or no liability ofinjuring the stock. In accordance withthis invention the leather to beskived is fed forward by an endless feeding belt, and an upperpositively driven feed wheel, and the material is held pressed down uponsaid feeding belt by oneor more presser feet. A block is adj ustablysupported beneath the feeding belt, at the point where the skiving is tobe done, the axis of which is at right angles to the axis of thepulleysover which the belt passes, said block presenting a hard surface overwhich the feeding belt travels, and by its adjustment varies the planeof the upper surface of said belt at the point where the 0 skiving isbeing done. Inv order that the skiving may be done as nearly as possibleover the driving pulley of the endless feeding belt, said pulley isprovided with a circumferential groove, and the block is placed in orenters said groove. A rotary ski'ving knife is provided, which isslightly tipped at an angle to produce the required bevel, the shaftcarrying it being mountedin a head which is made horizontally adjustableon an 40 arm on the frame. One of the pulleys over which the endlessfeeding belt passes is positivelydriven, and the other pulleyissupported by an adjustableframe, so that it may bemoved away from the.positively driven pul- 4' 5 ley to thereby tighten the belt. I, Theshaft of the positively drivenv pulley is supported by an adjustablebell-crank lever, or other form or construction of frame, so that it maybe raised or lowered at will. The shaft of the upper feed wheel is alsosupported by said adjustable frame. vided for the front of the rotaryknife, and

Suitable guards are proalso for-the back of said knife, and also atother places as will be described, to prevent the material which isbeing skived from coming in contact with any of the operating parts.

Figure 1, shows in side elevation a leather skiving machine embodyingthis invention; Fig. 2, a front elevation of the machine shown in Fig.1; Fig. 3, a vertical sectional. detail .showing the adjusting devicefor the driving shaft; Figs. 4, 5,'and .6, details of the endlessfeeding belt; Figs..7 and 8, plan andfront views of the supportingpulleys for the vendless feeding belt; Fig. 9, a vertical section of thepresser foot; Fig; 10, a side view of the adjusting device of thedriving shaft; Fig. 11, a plan view of one of the) guards of the rotaryknife; Fig. 12, a plan view of another guard to be referred to; Fig. 13,a vertical sectional detail of the adjusting device of the upper feedwheel carrying shaft.

The main frame work comprises essentially the base A, and oppositelyextended arms B, B, erected thereon. The shaft a, at one end of whichthe belt pulley a is'secured, has its bearings atthe end of thehorizontal arm of a bell crank lever or frame c see Figs. 3 and 11,which is contained within the hollow base A, and pivotedat each end at ato the side walls of said'base. A yoke of, is loosely connectedto thelower end of. the vertical arm of said bell-crank lever or frame a whichhas loosely connected to it a similar yoke to which an adjusting screw ais swiveled, said screw passing through an internally screw threadedhole in the side wall of the base A, and provided with a milled head bywhich it may be turned to adjust the position of said bell-crank leveror frame a raising or lowering the horizontal arm thereof, andtherebyraising or lowering the shaft a. The shaft a, has secured to its end,opposite the belt pulley at, a pulley b, see Figs. 2, 7, and 8, hereinrepresented as having a circumferential groove 19', and also a radiallyprojecting flange 12 An idler o is loosely mounted on a stud oprojecting from an arm 0 securedto the base A by a screw 0 the shank ofsaid screw passing through a slot 0 in said arm so that when said screwis loosened the arm may be adjusted longitudinally to in turn move theidler toward or from: the pulley 12., An. adj ust-ing screw 0 passesthrough a projection 0 on the base A, which bears against the end of thearm 0 by means of which said arm is adjusted longitudinally when thescrew 0 is loosened. To facilitate tightening said screw 0 it is hereinshown as provided with a finger piece 6 A feed belt passes around thepulley b, and idler e, the upper or outer surface of which is beveled atits inner edge as at d, and cut away or thinned at its opposite edge asat 0?, thereby leaving a central raised portion. This feeding belt ismade of leather, and by adjustment of the idler c it may be heldsufiiciently taut. A block or plate e is pivotally supported by an arm cwithin the circumferential groove 1) of the pulley b, said armprojecting from a post 6 cast integral with or secured to a plate a andan adjusting screw e passes through a projection on said post a, thetapering end of which bears against the under side of said plate c,acting to rigidly hold said plate c with its upper surface in differentplanes. The plate e bears against the under side of the feeding belt 01at the point where the skiving is to be done, and the upper surface ofsaid plate is curved as shown in Fig. 8, to afford a smooth andunyielding bearing over which said belt may travel. The rotary knife fis secured to the lower end of a shaft f supported vertically inhearings in the head f said shaft having at its upper end a belt pulleyf The knifefis supported at a slight angle with relation to the feedingbelt cl so that as the material is fed along it will be skived off on acontinuous bevel. The head f is mounted upon a screw 0 passingtransversely through the end of the arm 13, so that as said screw isturned said head will be adjusted horizontally. The head f also supportsthe shaft carrying the grinding disk 0. The upper feed Wheel 9 issecured to a shaft g lying parallel with the shaft a, and having itsbearings in a yoke or arm g pivoted at one end as at 9 to a bifurcatedvertical projection 9 rising from the horizontal arm of the bell cranklever a just above the shaft a, and

supported at its other end upon a spring 9 contained within a bifurcatedvertical projection 9 also rising from the horizontal arm of the bellcrank lever, just above the shaft a,a socketed adjusting screw g passingdown through a cross piece 5, secured to the top of said projection g,and containing a spiral spring which bears upon the arm g A toothedwheel 9 see dotted lines Fig. 1, is secured to said shaft g which isengaged by a toothed wheel 9 secured to the shaft a. The feed wheel g isadapted to bear upon the material on the feeding belt d, close to theouter edge of the raised central portion of said belt. A presser foot isadapted to bear upon the material at the raised central portion of thefeeding belt or directly above the block or plate e,said presser footbeing herein shown as a plate It secured to a post It by screws 2 orotherwise, see Figs. 1 and 9, the lower end 71. of which is bent orformed as a hook to pass beneath and partially embrace the shaft 9', andpresent its under surface to the material. The yielding pressure of thefoot is varied by a cam k bearing against one side of the plate h at thepoint where it is bent, and as said cam is adjusted vertically thehook-shaped lower end h of the plate will be moved in the arc of acircle, to thereby exert greater or less pressure upon the material. Thecam h is formed integral with or secured to a bar If, moving verticallyon the screws 2, as guides, and is also formed integral with or securedto a block 71. contained in a vertical recess in the post h, the upperend of said block being reduced in diameter or provided with a stemwhich is encircled by a spiral spring 7L5 bearing at its lower end uponthe block 71;, and at its upper end against the adjusting cap h which isscrewed into the upper end of the recess in the post. ing but h in oneor the other direction the cam 71/2 will be raised or lowered, therebymoving the hook shaped end it" of the plate. Another yielding presserfoot 19, also preferably adjustable is secured to the plate h, and postIt, by screws 6, or otherwise, its foot bearing upon the material abovethe cut away portion (Z of the feeding belt, or at the front side of theblock or plate 6. The post h is formed integral with or secured to anarm 71 which is secured to the end of the arm B of the frame. Numerouspins 3, project downwardly from said arm '5 which elfectually close thespace between said arm and the bed of the machine, preventing a vamp orother thing which is being skived from passing through said opening. Alarge platej which occupies substantially a horizontal plane, and has acurved upper surface, is formed integral with or secured to the plate e,and a hub e is also formed integral with or secured to said plate a,which embraces the shaft a to give additional support for the platej.This platej, in addition to serving as a support for some of the parts,also serves as a guard for the material being skived, directing it insuch a manner that it shall not engage with the operating parts of themachine. A guard is secured to the post h which protects the front edgeof the knifef. As a guide for the material which is being skived Iemploya suitablyshaped projection a formed integral with or secured to acurved plate at which incloses a portion of the feeding belt (Z and hasa rearward projection 71 through which screws 4 pass, securing saidplate and guide to the guardj. To prevent the material which is beingskived from coming in contact with the back side of the knife, after ithas been skived, a guard m is secured to the base A which passes aroundand above the back side of said knife, its extremity overlapping theknife as shown in Fig.12. The radial flange b and plate 6, serve asguides for the feeding belt. As to adjustment of the essential operatingparts it will be seen that the knife is adjustable horizontally by screw0',

By turning said adjustpasses'is adjustable in the arc of a circle aboutthe pivot a as an axis, byscrew a,

therebyraising or lowering the feeding belt,

and that the block or plate 6 is adjustable to vary the angle of thefeeding belt by the screw e By beveling the inneredge of the feedingbelt, and guiding the material to be skived in line with the inner edgeof the beveled portion thereof, I am enabled to use a rotary knife,tipped at an angle, and mounted in its bearings above the belt, so thatit will revolve transversely to the material, and not come in contactwith the belt. And furthermore by providing the feeding belt with thecut away portion d sufficient space is afforded for the presser foot'pbeneath the front edge of the knife, to bear upon and assist in holdingthe material in position to be skived.

I claim- Y 7 1. ha leather skiving machine, the combination of twopulleys, an endless feeding belt at thereon, beveled at its inner edge,as at d, and cut away at its outer edge, as at (1 leaving a flat centralportion the full thickness of the belt, a rotary skiving knife, and twopresser feet, one bearing upon the stock upon the flat central portionof the belt, and the other bearing upon the stock at the cut awayportion (1 and an upper feed wheel, substantially as described.

2. In a leather skiving machine, the combination of two pulleys, anendless feeding belt d thereon,beveled at its inner edge, as at d, andcut awayat its outer edge, as at (1 leaving a fiat central portionthefull thickness of the belt, a rotary skivin g knife, an upper feedwheel bearing upon the stock upon the fiat central portion of the belt,and apresser foot bearing upon the material at the cut away portion dsubstantially as described.

3. In aleather skiving machine, an endless feeding belt, two pulleysover which it passes, the shaft 0. driving one of said pulleys, and theadjustable bell-crank lever supporting said shaft a, substantially asdescribed;

4:. In a leather skiving machine, the combination of endless feedingbelt, two pulleys b, 0, over which it passes, driving shaft 0. for thepulley b, an upper feed wheel g, driving shaft g for it, and anadjustable bell-crank lever or frame a supporting said shafts a and g,substantially as described.

5. In a leather skiving machine, the combination of an endless feedingbelt, two pulleys b, 0, over which it passes, driving shaft 0, for thepulley b, an adjustable bell-crank lever or frame a supporting saidshaft 0, an up-' per feed wheel 9, driving shaft g for it, a yokesupporting said shaft g pivotally connected at one end to said bell-crank lever, and adjustably connected at the other end with said lever,substantially as described.

6. In a leather skiving machine, the combination of an endless feedingbelt, two pulleys over which it passes, a rotaryknife, and two presserfeet, and an upper positively driven feed wheel between said presserfeet, substantially as described.

7. In a leather skiving machine, the combination of an endless feedingbelt, two pulleys over which it passes, a rotary knife, and a positivelydriven upper feed wheel, an adj ustable yielding presser foot h, h",passing beneath the shaft of the feed wheel, substantially as described.

8. In a leatherskiving machine, the combination of an endless feedingbelt, two pulleys over which it passes, a rotary knife, a posi- 8otively driven feed wheel, and a presser foot consisting of the plate Itbent at its lower end at h", to bear upon the material and pass beneaththe shaftof the feed wheel, the cam h for adjusting the lower end hspring 71, and, adjusting nut h, substantially as described.

9. In a leather skiving machine, the combination of an endless feedingbelt, two pulleys b, 0, over or around which it passes, one of which asb has a circumferential groove, a presser foot and a rotary skivingknife, and the block 6 entering the groove in the pulley b and pivotallyconnected to a fixed arm e the axis of said block being at right anglesto the axis of the pulley b and the adjusting screw e having a taperedend for varying the plane of the upper surface of said block, 6,substantially as described.

10. In a leatherskiving machine, the combination of a rotary skivingknife, and an endless feeding belt, two pulleys over or around which itpasses, aframe supporting one of said pulleys, adj ustable on an axis inline with the axis of theother pulley, whereby the feeding belt may bemoved toward and from the skiving knife, a feed wheel bearing upon saidfeeding belt supported by the aforesaid adjustable frame and therebymovable in conjunction with the pulley which is supported by it, anindependent block beneath and adapted to bear against the under side ofthe feeding belt, beneath the skiving knife, an adjusting screw foradjusting it on an axis at right angles tothe axis on which the pulleysrevolve, to vary the plane of said block with relation to the face ofthe pulley, and a support for said independently adjustable block mademovable in conjunction with the movable pulley, substantially asdescribed.

11. In aleather skiving machine, the combination of feeding mechanism, arotary skiving knife, arm B supporting it, and a vertical guard 1;, 3,placed between said arm and the the guard m passing around the backsideof and crossing the plane of said knife, substantially as described.

14. In a leather skiving machine, the combination of a rotary skivingknife, an endless feeding belt, two pulleys over or around which itpasses, a frame supporting one of said pulleys adjustable to vary itsposition relative to the skiving knife, a feed wheel bearing upon saidfeeding belt supported by said adj ustable frame, an independent blockbeneath and adapted to bear against the under side of the feeding belt,at a point beneath the skiving knife, means for adjusting said block onan axis at right angles to the axis upon which ANDREW J. TEWKSBURY.

Witnesses:

BERNIOE J. NoYEs, CHARLES E. ORooKER.

